This invention relates to a method for controlling one or more variables depending on several control inputs in order to minimize an error function in general and more particularly to an improved method of this type which is well adapted for controlling the mixture in a raw material mill in the manufacture of cement.
A method of this general nature is known from the German journal "Regelungstechnik und Prozess-Datenverarbeitung" 1972, No. 5, pages 190 to 198. It is proposed there to apply the minimizing method of Zangwill (Computer Journal, Vol. 10, No. 4, pages 67 and 68) and to implement it with a process computer because of the large mathematical effort required.